The Role of Chromosomes & Hormones Flashcards
What are chromosomes?
- Found in the nucleus of living cells & carrying information in the form of genes
- The 23rd pair of chromosomes determines biological sex
What are the characteristics of chromosomes?
- 46 chromosomes in the human body arranged in 23 pairs
- Chromosome structure for females is XX
- Chromosome structure for males is XY
- Babys sex is determined by the sperm that fertilises the egg
- Baby will be female is sperm carrys an X chro & will be male if it carry’s a Y
What does the Y chromosome carry?
- A gene called the ‘sex determining region’ (SRY)
- The SRY gene causes the testes to develop an XY embryo
- These produce androgens: male sex hormones.
What is testosterone?
- A hormone from the androgen group that is produced mainly in the male testes
- Associated w aggressiveness
What is the role of testosterone?
- Controls the development of male sex hormones during foetal development
- According to evolutionary explanation, high levels of testosterone are also linked to aggression because it is adaptive
What is oestrogen?
- The primary female hormone
- Plays an important role in the menstural cycle & reproductive system
What is the role of oestrogen?
- The female hormone that determines female sexual characteristics & menstration
- Oestrogen causes some women to experience heightened emotionality & irratibility during their menstural cycle
- This is referred to as pre-menstural tension (PMT)
What is oxytocin?
- A hormone which causes contraction of the uterus during labour & stimulates lactation making it possible for mothers to breastfeed their children
- It also reduces the stress hormone cortisol & facilitates bonding- for this reason reffered to as love hormone
- Oxytocin is released in massive quantities during labour & after childbirth & makes mothers feel ‘in love’ w their baby
The fact that men produce less of this hormone has fuelled popular stereotype that men are less interested in intmacy & closeness within a relationship- However evidence suggests that both sexes produce oxytocin in roughly equal amounts during amorous activites such as kissing & sexual intercourse
Give one strength of testosterone.
- Evidence supports the role of sex hormones in gender development even in mature males
Christina Wang et al (2000):
- Male hypogonadism is a condition caused by a mans testes failing to produce normal levels of the male sex hormone, testosterone
- Wang gave 227 hypogandal men testosterone therapy for 180 days
- Changes in body shape, muscle strength, sexual function, libido were all monitored across the period
- Testosterone replacement improved sexual function, libido, mood & significant increases in muscle strength were observed in sample
Study shows that testosterone exerts a powerful & direct influence on male sexual arousal, as well as physical development in adulthood
What was the counter point for research into testosterone?
Daryl O’Connor et al (2004):
- Increased testosterone levels in healthy young men
- There were no significant inreases in the interactional (frequency of sexual intercourse) or non interactional (sex drive) components of sexual behaviour in ppts
- Men involved also had no change to their aggression or anger levels during the investigation either
Suggests that additional testosterone may have no effect on sexual or aggressive behaviour - though it doesnt challange role of testosterone in early development
Give one limitation of the role of chromosomes & hormones in gender?
- OL of biological accounts is that they ignore the role of social factors in gender related behaviour
Geert Hofstede et al (2010)
- Claim that gender roles around the world are much more a consquence of social norms than biology
- Researchers equate notions of masculanity & femininity whether whole cultures are individualist or collectivist
- Countries that place individual competition & independence above the needs of the community are according to H more masculine in their outlook
- This would include advanced capitalist societies such as the US & the UK
- Consequently traditional masculin traits will be more highly valued within these societies
Challenges biological explanations of gender behaviour & suggests social factors may ultimately be more important in shaping gender behaviour & attitudes
Give another limitation of the role of chromosomes & hormones (biological factors)
OL of biological explanations:
- They are reductionist
- Accounts that reduce gender to the level of chromosomes & hormones have been accused of underplaying alternative explanations
- Ignores other explanations such as the cognitive - wld draw attention to the influence of thought processes such as schema & psychodynamic approach
- This suggests gender is more complex than its biological influences alone
